Field of the Disclosure
The present disclosure relates generally to imaging devices and finishers, and more particularly to those having media accumulator-ejector.
Description of the Related Art
Stapler finishing devices have long been using a rubber finger, belt drive media accumulator-ejector devices. As shown in FIGS. 1 and 2, the prior art media accumulator-ejector 10 is typically made up of a frame 12 having mounted thereon two parallel, rotatable shafts 14, 16, positioned transverse to a media path P. Three belts 20, 21, 22 are mounted to the shafts 14, 16 and driven by a motor 30 via a gear train 32 and rotate parallel to media path P. Attached to the belts 20-22 are respective aligned, outwardly protruding rubber fingers 23-25, that extend out through slots provided in a media accumulation plate 40 that is formed as part of a cover 42. In operation, media is fed from an imaging device onto the accumulation plate 40 to form a media stack MS positioned downstream of the aligned fingers 23-25. When the media stack MS has been formed, the motor 30 is energized to rotate the belts 20-22 which move the fingers 23-25 into contact the trailing edge TE of the media stack MS and push the media stack along the accumulation plate 40. As the belts 20-22 continue to rotate, the media stack MS is ejected from the accumulation plate 40 to be received at a finisher 50 where a stapling may take place.
This prior art design does exhibit some drawbacks. There is a limited speed point in ejection of the media stack. This is due to the fact that rubber insert fingers 23-25 tend to bend or flex when driving a heavy or tall media stack MS from the accumulation plate 40. Failed to eject issues arise when one or more of the fingers 23-25 miss catching the trailing edge TE of the media stack MS or catch only a portion of the media stack MS which can occur when the media sheets are curling upward. Also, there is limited capability for single media sheet pass through feeding. The prior art design uses a media accumulation process for all media with all job types, for example, stapling, non-stapled, offset, non-offset, flushing/standard stacking, before media stack ejection will happen. This wastes time and reduces throughput speed performance. Lastly, there is a manufacturing and service challenge to properly time or align the fingers 23-25 during assembly or after belt replacement.
It would be advantageous to provide a media accumulator-ejector that overcomes the stated drawbacks. It would be further advantageous to have a media accumulator-ejector that can more reliably handle media that has curled. It would also be advantageous to have a media accumulator-ejector that does not interrupt continuous individual sheet media feeding.